Local area networks (LANs), which couple separately located computers together, have become a common feature in today's workplace. A LAN cable, which physically spans the distances between computers and includes connectors and terminators installed thereon, serves a key role in the LAN. However, failures in a LAN cable can occur during installation, during modifications to the computer network, and when furniture, computer, or office space relocations occur.
Typically, even LAN cable failures which completely halt LAN operations can be difficult to identify and isolate. However, LAN cables experience many other failure or problem modes which are extremely difficult to identify because they lead to a degradation in performance rather than a complete halting of LAN operations. Skilled engineers and technicians can and do utilize a variety of currently available test equipment to troubleshoot such LAN failures and problems. However, today's workplace is often staffed by persons who, while highly skilled in various technical areas, do not possess the types of skills or equipment required to fully understand and identify the many complex electrical parameters which characterize a LAN.
Consequently, the troubleshooting of a LAN, even when a relatively simple problem is suspected, requires the services of such LAN-skilled persons using the appropriate test equipment. Many managers in the workplace dislike obtaining the services of such LAN-skilled persons because of the excessive computer down-time which may result from waiting for such persons to arrive and because of the large fees such persons demand.
Accordingly, the successful troubleshooting of common LAN failures by an internal LAN user would be a highly desirable alternative to obtaining the services of outside LAN-skilled persons. Unfortunately, the test equipment currently utilized in troubleshooting LAN problems assumes a large familiarity with the complex electrical parameters that characterize a LAN. Consequently, such test equipment fails to meet the troubleshooting needs of the typical LAN user. For example, such equipment typically includes sophisticated time domain reflectometry (TDR) circuits which require an equipment operator to enter a significant amount of data in order to perform a TDR scan of a cable under test. Specifically, an operator is typically required to characterize a nominal velocity of propagation (NVP) and an impedance of the cable under test. While the entry of such data presents no obstacle to a typical LAN-skilled person, the entry of such data is highly undesirable to the typical LAN user who does not readily know such data and may not fully appreciate the significance of such data to TDR.
In addition, such conventional equipment requires a user to enter a desired pulse width for use in connection with TDR scans. While this pulse width selection is readily understood and appreciated by the typical LAN-skilled person, the typical LAN user may not fully appreciate its significance in TDR and may have trouble in making an appropriate choice.
Conventional LAN testing equipment fails to serve the typical LAN user's needs in other areas. For example, such conventional equipment fails to include functions for performing simple continuity checks, for electrical interference testing, for locating cables which may be hidden in ceilings, walls, under carpets, etc., and for performing other common tests required in a typical computerized workplace, such as serial data port testing. Moreover, such conventional equipment typically presents information in a cryptic manner which requires a significant amount of interpretation on the part of an equipment operator. Furthermore, such conventional equipment often performs TDR scans slowly so that such conventional equipment cannot operate simultaneously with operation of the LAN. Still further, such conventional equipment fails to permit the saving of test data for later analysis or for later presentation to a LAN-skilled person.
In addition, such conventional equipment often assumes the availability of additional "test" equipment, such as chart recorders, oscilloscopes, VOM's, and the like. However, the typical LAN user may not readily possess such additional "test" equipment. Furthermore, such conventional equipment, especially when associated with supporting "test" equipment, often costs so much that a typical LAN user cannot afford to purchase it for emergency and occasional use only.
Thus, a need exists for cable testing equipment which addresses the needs of the typical LAN user.